Turret press



Aug. 14, 1945. w. ERNST 2,332,041

TURRET PRESS Filed March 1, 1941 5 Sheets-Sheet 1 .ITEr'l 59 u 03 so 2.0

I I 1 INVENTOR I l J WALTER ERNST 2;:- 6 BYQH I M I- ATTORNEY:

W. ERNST TURRET PRES 5 Aug. 14, 1945.

5 Sheets-Sheet 2 Filed March 1, 1941 is I JTE-E luvem'oa WALTER EmmATTORNEYS W. ERNST TURRET PRESS Aug. 14, 1945.

5 Sheets-Sheet 5 Filed March 1, 1941 R O T N I V N WALTER ERNST A YTORNEYS W. ERNST TURRET PRES S Aug. 14, 1945.

Filed March 1, 1941 5 Sheets-Sheet =4 II'TEB IuvemoR f wanna ERNST W.ERNST TURRET PRESS Aug. 14, 1945.

Filed March 1, 1941 5 Sheets-Sheet 5 Name {Rust Patented Au 14, 1945TURRET PRESS Walter Ernst, Mount Gilead, Ohio, assignor to The HydraulicDevelopment Corporation, 1110., Wilmington, Del., a corporation ofDelaware Application March 1, 1941, Serial No. 381,376

12 Claims.

This invention relates to presses and press control systems, and inparticular to turret presses having rotary turrets for feeding-the workpieces to the press.

One object of this invention is to provide a turret press in which arotatable turret may be angularly shifted by a predetermined butadjustable angle to allow the employment of various turrets with adifferent number of turret stations 4 in connection with one and thesame pressing plunger.

It is another object of this invention to provide a turret press inwhich hydraulic shifting means is provided, which is adapted both toshift the turret from one indexing position to another indexing positionand to hold the turret in the thus shifted position for a predeterminedtime.

A further object of the invention consists in the provision of a turretpress in which the turret is angularly reciprocated between twopredetermined positions and is automatically held in its respectiveposition until the pressing operation is completed.

Another object of the invention is to provide a turret press in whichthe initiation of a working stroke of the pressing plunger is controlledby the turret so that the pressing plunger can be operated only afterthe turret has been moved to a work indexing position.

Still another object is to provide a turret press in which the turret ishydraulically held in one and the same indexing position during twosubsequent working strokes of the pressing plunger.

A still further object of the invention is to provide a turret press inwhich the turret shifting mechanism may be used in connection withdifferently sized turrets so as to allow of a variation of turrets beingused in connection with one and the same press.

Another object of the invention consists in the provision of a turretpress in which the turret,

after completion of a working stroke, is shifted to a predeterminedposition in which a fluid operable extracting mechanism may extract thework piece from the turret.

These and other objects and advantages of the invention will appear moreclearly from the following specification in connection with theaccompanying drawings, in which:

Figure 1 illustrates a front view of an embodiment of the invention.

Figure 2 is a section along the line 22 of Figure 1 and shows a top viewof the turret.

Figure 3 is a section along the line 3-3 of Figure 1 and shows two upperdies connectei to the platen.

Figure 4 is a vertical section along the line 4- of Figure 5 andillustrates the lifting mechanisn for the turret.

Figure 5 is a longitudinal section along the lin 55 of Figure 1.

Figure 6 illustrates the mechanism for angu larly shifting the turret.

Figure 7 is a diagrammatic cross sectioi through a typical work pieceready for the press ing operation in the turret press according t theinvention.

Figure 8 shows the work piece of Figure after the completion of thepressing operatior Figure 9 shows the complete hydraulic an electriccircuit for the press of Figure 1.

Figure 10 shows another electric circuit whic] may be used in connectionwith the hydrauli circuit of Figure 9 for a simplified control of thpress.

General arrangement In general, the turret press of the present invention consists of a press frame having a be and a head interconnectedby strain rods and rotatable turret between said strain rods. Th turretis normally supported upon the bed c the press during the pressingoperations but 1' raised from the press bed and into engagemer withanti-friction bearings during its rotatin or indexing operation. Afterthe indexing opera tion has been completed the turret is brougl again torest upon the press bed, thereby re moving the load from the turretbearings s button.

The invention comprises a control system which, without effecting anychanges in the structure of the press or in the control system, mayselectively be operated so as to cause the pressing platen to performtwo working strokes during one and the same indexing operation of theturret or, if desired, only one working stroke during the same indexingoperation of the turret. This control system includes a four-way valvewhich, responsive to the movement of the platen, controls the supply ofpressure fluid to a fluid motor actuating a die carrier with a pluralityof dies.

The press according to the invention is furthermore so constructed as toallow the substitution of one turret for another turret whilemaintaining the shifting and lifting mechanism for the turret. Theturret shifting-mechanism is furthermore adapted to effect annularreciprocation of the turret by a predetermined but adjustable angle sothat in case the turret comprises four stations it may be rotated by 90degrees only, while in case the turret comprises two stations only itmay be rotated by 180 degrees.

Structural arrangement Referring first to Figure 1, the press illustratetherein comprises a press bed and a press head 2| interconnected witheach other by strain rods 22 and nuts 23. Normally supported by thepressbed 20 is a turret 24 which comprises a central member 25 connectedatits upper end, for instance by screws 26, with a top portion 21 andconnected at its lower end with a bottom portion 28. The top and bottomportions 21 and 23 are interconnected with each other by side portions29. The various portions of the turret may be connected together bywelding or in any other convenient manner.

The top and bottom portions 21 and 28 comprise openings 30 and 3|respectively in which according to the embodiment of Figure l aremounted four turret stations 32 (Figure 2). Each of these turretstations is suiilciently strong to sustain the pressing force of theplaten 33 which carries two upper die members 34 cooperating withcorresponding lower die members 35. The lower dies are supported andheld in position on the turret by plates 36 and ring members 31. Thetubular turret stations 32 are provided with bores 38 closed at theirlower ends by the head members 38 (Figure 5) having bores 40 forreceiving the ejector mechanism subsequentlydescribed. The turretstations, when in pressing operation, rest upon supporting blocks- 4iprovided in comespondingly shaped recesses 42 in a bolster plate 44which in its turn rests upon the bed 28. lhe bolster plate 44 is rigidlyconnected to the bed 20 in any convenient manner.

The central member 25 o! the turretfl' -com- ,prises a cylinder 43cooperating with a piston 45 therein which, by means of the pistonrod'46'with rangement is such that when pressure fluid is introducedinto the conduit 50, it passes througl the piston rod 46 and piston v45into the uppei portion of the cylinder 43, thereby lifting the turretuntil the piston 45 abuts the anti-friction bearing 52, whereupon thelifting operation of thi turret stops.

The turret 24 also carries an annular gear ring 53 meshing with a pinion54 which is drivingl: connected with a pinion 55 (Figures 5 and 9)'which in its turn meshes with a rack 56. Thi gear ring 53 has such aheight that it remaim in mesh with the pinion 54 also when the turre isin lifted position. The rack 55 is guided ir guiding members 51, 58respectively connected t( the cylinders 58; 50.

Reciprocably mounted in the turret shifting cylinders 50, 80, areplungers 6.1, 82, which may be integral with each other or consist oftwo portion: rigidly connected with each other. Movably connected withthe plungers GI, 62 is a supporting member 53 which is rigidly connectedto the racl 56 so that movement oi the plungers 5|, 82 effect: movementof the rack 56.

The cylinders 53, 80 are adapted to be suppliei with fluid pressure forselectively moving th plungers 6|, I 82 in one or the other directionEach of the plungers 8|, 82 has at its free end i tapered recess 18, H,adapted to cooperate witl adjustable bolts 12, 13 which, when theplunger. 8|, 82 approach the end of their extreme right hand andleft-hand position respectively, onto the said recesses, thereby causinga cushionim effect. The adjustable bolts 12, 13 are also adapter tolimit the stroke otthe plungers SI, 52.

To prevent leakagefrom the cylinders 58, it their inner ends are closedby packing materia l4 compressed by glands 15.

As will be clear from the above, movement 0 40 the plungers 51, 62 inone or the other directiol tion by a predetermined angle, in theparticula its flange 41, is rigidly connected to the bolster plate 44 bymeans of the nut 48. The piston rod 48 has a bore 49 therein (Figure 9)which passes through the piston 45, thereby communicating with the upperportion of the cylinder 43. The bore 48 is connected to a conduit 50which leads to the hydraulic system, which will be described later.

To prevent leakage from the upper portion of the cylinder 43 to thelower portion thereof, the piston 45 is provided with a sealing ring 5|.Also provided in the cylinder 43 at the bottom portion thereof is ananti-friction bearing 52. This arinstance in the embodiments of Figures1 and i by 90 degrees. In other-words, according to th embodiments ofFigures 1 and 2, the plane througi the axes of the ejector cylindersforms an angle 0 90 degrees with the plane interconnecting the axe ofthe upper dies 34.

Reciprocably mounted inv the ejector cylinder 16 is a plunger 11 with anejector rod 18 adapte to pass through a bore 18 in the bolster plate 4and to engage a work piece supporting membe in the turret stations 32.The supporting mem ber 80 supports the work piece 8! and an inne die,generally designated 82, preferably made u of a plurality of individualblocks 83 so that th height of the inner die may be easily varied. Thlower portion of the ejector cylinders 15 commu nicates with a conduit84 (Figures 5 and 9) whil the upper portion of the ejector cylinders communieates with a conduit 85.

To prevent leakage from the ejector cylinder 15, packing material 85 isprovided adjacent th upper end of each ejector cylinder and is compressed between a ring member 81 threadedly con nected to the cylinders16 and a closure member 83 connected to the respective cylinders I6 bymeans of screws 89. The ejector rod 18 is adapted partially to lift thefinished work piece out or the respective turret station, whereupon itmay be fully extracted from the said turret station by means of a fluidoperable lifting device 90. This lifting device consists, according tothe showing in Figures land 5 of a fluid cylinder 9I having reciprocablymounted therein a double-acting piston 92 connected with a piston rod 93which at its upper end carries a hook-shaped gripping member .94. Thegripping member 94 is shiftable about the piston rod 93 so that it caneasily be swung into engagement with a finished work piece for liftingthe same out of its respective turret station andafter the liftingoperation thereof has been completed can then be shifted by a desiredangleto unload the work piece, for instance o'na conveyor or the like.-

The-upper and lower portions of the cylinder 9I communicate respectivelywith a conduit 95 and 96 leading toa four-way valve 91, whichcommunicates with a fluid source by means of conduit 98 and with anexhaust by means of conduit. 99. ,Thevalve 91 may be operated in any..convenient' manner, for instance by actuating a foot pedal, frofacilitate the lifting operation,

.the pressplaten 33 comprises recesses IM and I: which register with theturret stations in their ejecting position. Q I

. The ,platen33; is'connected to a ram I03 reciprocably mountedin,thepress cylinder I which is provided, with a surge valve I adaptedselectiveiyto admitdiuid from a fluid tank I06 into lthecylinderfl04 or.vice versa. The surge valve I05 doesnot form a partof the presentinvention and for a morev detailed description thereof referencemay behad to U. S. Patent No. 2,193,248 to Ernst. -,The surge valve I05 servesto preflll the. cylinder I04 when the ram I03 moves downwardly bygravity. Hydraulically connected with the surge valve,I05 is a conduitI01 communicating with a conduit I08 which comprises a pressure relief.valve I09 and a check valve IIO adapted to allow fluid to pass from thefluid tank I06 into the conduit I08 but not vice versa. Branching offfrom the conduit I 08 is a conduit III leading to the main cylinderrelease and pump bypass valve I I2. This valve which serves tofacilitate the initiation of a retraction stroke by releasing thepressure in the cylinder I04 does not form a part of the invention andmay be of the type described in U. S. patent application 286,063 toErnst, filed July 24, 1.939, which has matured into Patent No.2,263,205. Also communicating with the valve H2 is a conduit II3comprising a pressure relief valve I I4 and communicating with a conduitII5 leading to a conduit II6, one end of which communicates with themain cylinder release and pump by-pass valve II2, while the other end ofconduit II6 leads to a conduit Ill. The conduit I I1 communicates on onehand with the cylinder I04 and on the other hand with one side ofareversible variable delivery pump I I8.

:Branching off from the conduit H1 is a pilot line II9 leading to aservomotor I20 for the variable delivery pump II8. Also communicatingwith said servomotor is a pilot line I2I leading to a conduit I22 whichis connected with the other side of the variable delivery pump H8. Theservomotor I20 is adapted, in response to a predetermined pressure inthe lines H1 or I22, to shift the pump to substantially no-deliveryposition. The conduit I22 leads to apush-back cylinder I23 andcommunicates with the conduit I08 and a conduit I24 leading to apush-back cylinder I25. Reciprocably mounted in the pushback cylindersI23 and I25 are push-back plungers I26 and I21. connected with theplaten 33 for effecting the retraction stroke of said platen and the ramI03. The platen 93 has an arm I28 cooperating with the free arm I29 of athree arm lever, generally designated I30 and shiftable about the pivotI3 I The lever I30 is operatively connected by means of its arm I32 andthe link I33 with the armature I34 of a solenoid I35, while the arm'I36of the lever I30 is connected by a link system I31 with the flow controlmember of the variable delivery pump I I8 in a manner well known'tothose skilled in the art so that energization of the solenoid I35 movesthe pump II8 to full delivery forward stroke position while, when thesolenoid I35 is de-energized, a spring in the servomotor I33 connectedwith the pump II8 urges the pump to full delivery retraction strokeposition. Servomotors of the type referred to above for controlling'thepump II8 are well known in the art and'may be of the type disclosed inU. S. Patent No.' 2,'184,665 to Ernst. Branching ofl fromthe conduit H1is furthermore a conduit I39 leading to a tonnage control 1 valve I40which, responsiveto a predetermined pressure in the conduit I39, opensaswitch, the

- terminals of which are connected'with lines I and I42 respectively.As'soon as the pressure which has caused the opening of saids'witch inthe tonnage control valve decreases, the said switch automaticallycloses again. Tonnage control valves of this type are well knownin theart and are described, for instance, in the U. sgratent No. 2,224,957 toErnst. v

The line I4I comprises normally closed switches I43 and I44 and leads tothe main supply line I45. The switch I43 is an over travel safety switchand is adapted to be engaged by the platen 33 so as to be opened therebyin case due to an accident, for instance cracking of the work piece,thenecessary pressure for operation of the tonnage control valve I40 shouldnot develop and the platen should move beyond a desired point,

The line I42 communicates with a contactor coil I46, the energization ofwhich controls the movement of the armature I41 with the blades I48 andI49. The contactor coil I46 is adapted to be connected with the mainsupply line I50 by closure of the starter switch I5I. Also connectedwith the coil I46 is a line I52 which, by closure of the blade I43, maybe connected with the line I53 leading to the main supply line I50.Closure of the blade I49 effects communication between the line I54connected to the line I53 and the line I55 connected to the line I56.The line I56 connects one end of the solenoid I35 with one end of thesolenoid I51, while the other end of the solenoid I51 is connected bylines I 58'and I59 with the other end of the solenoid I35.

Energization of the solenoid I51 controls the movement of an armatureI60 which is connected with a double piston valve member iii of afourway valve, generally designated I62. The arrangement is such thatenergization of the solenoid I51 moves the valve member I6I towardtheleft with regard to Figure 9, while when the solenoidmisde-energized, a spring I63 moves the valve member I6| toward the right.The fourway valve I62 communicates with the conduits 94 andandfurthermore communicates with a conduit I64 leading to a conduit I05which is con- I'IIconnected to a four-way valve I12 which is alsoconnected with the conduit I65. The fourway valve I12 is similar to thefour-way valve I62 and has a double piston valve member I13 which ismoved by energization of the solenoid I14 in one direction and urged byspring I15 in the opposite direction.

Also communicating with the four-way valve I12 are conduits I16 and I11respectively leading to the turret shifting cylinders 59 and 60. One endof the solenoid I14 communicates by means of the line I18 with the mainsupply line I50, while the other end of the solenoid I14 communicateswith a line I19 adapted by closure of switch blade I80 to be connectedwith the line I8I leading to the main supply line I45.

Operation I It may be assumedthat all parts of the'press occupy theposition shown in Figure 9. and that it is now desired to perform apressing cycle. To this end, two operators, working on different sidesof the press, insert the inner dies 82 and work pieces 8| into theturret stations 32 which register with recesses IOI, I02 in the pressplaten133; v'I'hereupon the switch blade I80 is actuated so-astoefiectinterconnection of the lines I18 and.I 84.

a result'thereof, current flows from the main supply; line I45 throughlines I8I, I18.solenoid I14 and line I18 to the mainsupply line I60,thereby energizing the solenoid I14 and shiftin the valve member I13toward the left.

Assuming that previously the auxiliary pump I66 has been started, nuidpressure will flow-from the pump I66 through lines I65 and. I16 into theturret shifting cylinder 58, while the turret shifting cylinder 60 willbe connected through line I 11 with the exhaust line "I. -As a result,the fluid pressure acting in the .cylinder 58 moves the plungers BI and62 toward the right and, thereby, alsothe-rack 56, which movement, bymeans of pinions 55. and, is conveyed to the gear ring 53 connected tothe turret 24 so as to rotate the turret which, at-the end of its-laststroke, was moved into its-;lifted-position. When the bolt 13 engagesthe'bott'omof the recess H in the plunger 62, the rack-56,;and 'therebyalsoithe turret 24, comes toa stopz The turret 24 has now been shiftedby 90 degrees so that the Just loaded turret stations now register withtheup'per dies 34 on the platen 33, while theturret stations previouslyin alignment with the upper dies 34 and containing completed work pieceshave now been moved into position where they register with the ejectorrods'18.

Due to the fact that the pump I66 holds its pressure in line I85, therack 56 is positively held in its shifted endposition, thereby alsoholding the turret in its last shifted position.

To initiate the pressing operation, the normally open starterswitch I 5Iis now closed so that current flows from the main supply line 5 throughthe normally closed switchesl, I43, line I,

tonnage control valve I40, contactor coil I46 and switch I 5I to themain supplyline I53. As a result thereof, the coil I46 is energized andcauses the blades I48 and I48 to move to closing position. The blade I48establishes a holding circuit for the coil I46, which holding circuitcomprises main supply line I45, switch I44, I43, line I, tonnage controlvalve I40, line I42, coil I46, line I52, blade I48 and lines I53 andI50.

The blade I48 closes the circuit comprising the lines I50. I53, I54,blade I49, line I55, solenoid I35, lines I58 and 145. Simultaneouslybyway of lines I56 and I58 it also closes a circuit through the solenoidI51 which is arranged in parallel to the solenoid I35. Energization ofthe solenoid I actuates thelever I30 and by means of the link system I31puts the pump II8 into full delivery forward stroke position.

Energization of the solenoid I51 causes the valve IN to move toward theleft so that pressure fluid from the pump I86 flows through eonduitsI65, I64, valve I62, conduit 84. into the lower portion of the ejectorcylinders I6, thereby moving the ejector rods 18 upwardly .and partiallyliftingthe completed work pieces out of their respective turretstations. The operators may then shift the'gripper arms 54 beneath thehead of the. completely finished and now partially ex- I00. cause fluidpressure to enter beneath: the

piston 82 for moving the grippers 84 upwardly to fully extract the workpieces. The completed work pieces may then, by shifting of'thegrippers54 and moved into alignment with the respective turret stations,whereupon, by operationof the valve 81, fluid-pressure maybe'introducedabove the piston 82 so as to'lo'wer the grippers 94 and '40 thereby thework pieces into the empty' turret stations. The grippers 64 are thenmoved out of alignment with thejust loaded turret stations.

While this loading and unloading is being per- .formed, the ram I03moves downwardly by gravity and fluid is, delivered by thepum II6 intothe cylinder I04, which is supplemented by fluid passing from the tankI06 through the surge valve I05. Fluid from the push-back cylinders I23and I25 escapes through the line I24 to the line I22, which is now thesuction line-of the pump II8,"while any excess fluid may escape throughthe conduit I08 and the pressure reducing valve I09. 4

As soon as the upper dies 34 engage the work pieces 8I, pressurebuilds-up in the cylinder I04 so that the surge valve I05 closes. Whilethe ram I03 now further advances, the engagement of the upper dies withthe work pieces carried by the turret causes the turret to move from itslifted-position downwardly until the turret stations 32 rest upon thesupporting blocks 4I, in which position theantifriction bearings 52 arerelieved of any load of the turret while the load of the turret is nowtaken up completely by the bolster plate 44 and press bed 20. Thefluidexpelled from the upper portion of the cylinder 43 escapes through thebore 48 and conduit 50 into the conduit I24 from where it may flow toconduit I 22, which is now the suction side of the 'When-at the end ofthe actual pressing stroke a predetermined pressure has 'built up in thecylinder I04, It actuates the tonnage control valve I40 so as tointerrupt the electric connec-' tion between the lines I and I42. Thisbreaks the holding circuit for the coil I48 so that the spring I82 nowopens the switch-blades I 48and I49. This also breaks the energizingcircuit for the solenoid I35and the solenoid I61.

De-energization of the solenoid I35 causes a spring in the servomotorI33 of the pump II8 to move the latter to full delivery retractionstroke position so that pressure fluid is delivered by pump II8 into theline I22 and thereby into the push-back cylinders I23 and into the upperportion of the turret cylinder 43. Consequently, while the platen 33 isnow moved upwardly, also the turret 24 is lifted.

at the end of the retraction stroke by -a stop, in which case the pump,inre sponse, to a predetermined fluid pressure in theqconduit I22,-would be moved to substantially,no-delivery position by fluid pressugeconveyed fromgtheconduit I 22 through thepilot line. I2I totheservomotor I20.

All parts of thepress now occupy-the'position shown in Figure 9 with theexception that-the switch I80 is -in closedposition ,and that theplungers BI and 62 are in their'right-hand-posttion. The press .is thenready for a new. cycle,

which may be initiated by opening. of the'switch I80 so thatthe springI16 moves -thevalve member I 13 to a position in which fluidpressurepasses through the conduit I11, -thereby shifting the rack 56 towardtheleft so as to rotate theturret 24 into a position in. which the justcompleted work pieces register with the ejectors, while the work piecesloaded during the last pressing stroke are moved into pressing position.

Alternative electric circuit While in the arrangement of Figure 9 twoswitches, namely I80 and I5I, are subsequently to be actuated forperforming a complete cycle comprising the indexing operation and thepressing operation, it may happen that the proper order of actuating theswitches I80 and I5I is accidentally reversed'so that the ram starts itsdownward movement wh Lle the turret has not been shifted so that thepreviously completed work pieces are still in their pressing position.While no harm would be done to vthe work pieces-as long as they remainin their pressing position. there would still be a valuable loss of time'until the ram has been returned to its initial position.

However, if the error should have been noticed and it would be tried,during the downward stroke of the ram to shift the turret, theworkpieces completed during the last pressing operation may be damaged.In order to avoid accidental reverse of the proper sequence of operationof the switch I80 and the switch I5I, the electric circuit shown inconnection with Figure 9 may be replaced by the circuit of Figure 10,while the turret shifting cylinders 59, 60, may be supplemented byswitches as shown in Figure 6. Referring to Figure -6, it will be notedthat each end of the rack 56 carries an adjustable abutment screw I83.I84 adapted respectively to close electric switches, generallydesignated I85, I88. The switches are norm held in open position bymeans of springs I81, respectively.

It is of course understood that, if desired, e of the adjustableabutment screws I83, I84 I constitute a contact of the switches I85, I86spectively, in which case the springs I81, I 88 1 be omitted. Theswitches I85, I86 form a 1 of the electric control circuit of Figure 10.Figure 10 the main supply lines are again de: nated with the numeralsI46 and I50.

Connected with the main supply line I line I89 are two terminals I90 andI9I adar selectively and respectively to be connected the starter switchblade I92 with the termix I83, I94. The starter switch blade I92 is rmally held in its intermediate position, for stance .by springs (notshown). The termi I93 is connected by a normally closed can switch I85with a line I96.

The line I96 leads to one end of the soler I81, which latter takes theplace of the soler I14 in Figure 9 and is adapted, when energi; to shiftthe valve member I13 of the four-\ valve I12 to the right. The other endof solenoid I91 is connected with the main sup line .I50. The line I96is also connected it one endof the solenoid I98 which correspond: thecontactor coil I46 of Figure 9. The other I of the solenoid I 98 isconnected by means line I99 to the main supply line I50. Furth.moreconnected with the line I96 is a line adapted, in esponse to theenergization of solenoid I 98, to be connected by the norm:openswitchblade 20I with the line 202 OOmDJ ing the normally closedtonnage control swi 203. The line 202 is connected with the m supplyline I45. Energization of the solenoid also causes the normally openswitch blade 1 to close, thereby interconnecting the line 205 w the line206.

The line 206 connected to the main supplyl I comprises the normally openswitch I86 wh is adapted to be closed by rightward moveml of the rack 56(Figure 6). Connected to the l 205 is one end of a solenoid 201, theother end which is connected to the main supply line I The solenoid 201fully corresponds to the sc noid I51 controlling, in cooperation with 1spring I63, the movement of the valve I62 whl in its turn, controls theoperation of the ejectr Also connected with the conduit 205 is one endthe pump solenoid 208, the other end of wh is connected with the mainsupply line I43. '1

solenoid 208 fully corresponds to the solenoid of the embodiment ofFigure 9.

The terminal I 94 which, as mentioned above adapted to be connected bythe starter swia blade I92 with the terminal I 9|, is connected line 209with the normally closed control swii 2I0, which is shown in thedrawings in open 1 sition, into which it is moved by a cam 2I I theturret 24 (Figure 2) when the turret 1 reached one indexing position.When the tur leaves this indexing position, the control swii 2I0 closes,while the cam 2 opens the norms closed control switch I when the turret1 reached its other indexing position.

In closed position the control switch 2I0 cc nects' the line 208 withthe line 2I2 which lez to'theline 2I3. The line 2I3 is connected w oneend of a valve shiftingasolenoid 2I4 whil when energized, takes theplace of the spri I15 in the embodiment of Figure 9. The otl end of thesolenoid 2 is connected with I main supply line I50. The 'line 218 isfurthermore connected with one end of -11 solenoid 2I5 controlling theoperation of switch blades 2| 6 and 2" so that energization of thesolenoid 2I5 causes the switch blade 2; to connect line 2I3 with theline 2I8 connected to the line 202.

Energization of the solenoid 2| also causes the blade 2" to connect theline 2I8 with the line 220'. The line 2I9 is connected with the line205, while the line 220 is adapted to be connected with the line 22I,leading to the main supply line I50, when the switch I85 (Figurefi) isin closed posi-- tion, as shown in Figure 10.

Operation of alternative electric circuit Supposing that the mechanicaland hydraulic parts of the structure in Figure 9 occupy the positionshown therein, and that the electric circuit of Figure 9 has beenreplaced by the electric circuit of Figure 10, the device operates asfollows:

To start a cycle, the starter switch blade I92 is actuated tomomentarily efl'ect connection between the terminals I90 and I93.Current will then flow from the main supply line I45 through line I89,starter switch blade I92, control switch I95, line I96, and from there,on one hand through solenoid I91 and the main supply line I50, and onthe other hand through solenoid I98 and line I99 likewise to the mainsupply line I50. As a result thereof, the solenoid I91 and I 98 areenergized.

Energization of the solenoid I91, which, as previously mentioned, takesthe place of the solenoid I14 of Figure 9. shifts the valve I18. so thatfluid pressure from the auxiliary pump I88 passes through the conduitI18 into the shifting cylinder 59, where it moves the plungers 8|, 82and, thereby, the rack 58 toward the right. This-movement is conveyedthrough the pinions 55 and 54 to the gear ring 53 so as to effect anindexing operation of the turret as previously described in connectionwith Figure 9.

Energization of the solenoid I98 causes the blade ml to interconnect theconduits 200 and 202, thereby establishing a holding circuit for thesolenoids I91 and I98. Energization of the solenoid I98 furthermorecauses the blade 204 to interconnect the line 208 and the line 205.However, no circuit is closed thereby, since the switch I88 is held openby the spring I88. In the left end position of the rack 58 the switchI85 was closed by the screw I83 against the thrust of the spring I 81,while in the corresponding position of the turret 24 the cam 2 held thecontrol blade 2I0 open. When now, due to the energization of thesolenoid I91, the rack 58 moves away from its left end position, therebyalso causing the turret 24 to leave its last indexing position, thespring I81 opens the switch I85, while the control switch 2 I0 closes.In other words, while the rack 53 is intermediate its two end positions,both control switches I95 and 2I0 are closed, while the switches I85 andI88 are open. Closure of the control switch 2I0 is without eflect atthis time of the cycle and so is the opening of the switch I85.

When the rack 58 has reached its right end P sition, it closes theswitch- I 88, while the turret has moved to its new indexing position,in which the cam 2| I has opened the control switch I95. Since, asmentioned before, the solenoids I91 and I98 are held energized throughblade 20I, the opening of the control switch I95 has no effect on thesolenoids I91 and I98 and, therefore, has no effect on the position ofthe valve member I18 -a predetermined and of the rack 58, which latteris consequently held in its new position due to the pressure fluid inthe line I18. Closure of the switch I88, however, establishes a circuitthrough the pump solenoid 208 and the solenoid 201 which controls thevalve I82. This circuit comprises the line I50, now closed switch I88,line 208, blade 204 and line 205, from where the current flows, on onehand, through pump solenoid 208 and. on the other hand, through thevalve solenoid 201 to th main supply line I45.

Energization of the pump solenoid 208 causes actuation of the lever I80which shifts the main pump II8 to full delivery forward stroke position.The ram I03 then starts its downward stroke as described above inconnection with the operation of the electric circuit shown in Figure 9.Energization of the valve solenoid 201 causes the valve member I8I tomove so that fluid pressure from the auxiliary ump I88 passes below theejector plungers 11 so as to lift the ejector rods 18 and cause the samepartially to lift the previously completed work pieces from therespective turret stations- The completed work pieces may then beremoved and replaced by new work pieces as likewise described above inconnection with the structure of Figure 9,

As soon as, at the end of the pressing stroke, pressure is obtained inthe press cylinder I04, this pressure is conveyed through the conduitsIII and I89 to the tonnage control valve I40, thereby opening thetonnage control switch 208. This breaks the holding circuit for thesolenoids I 91 and I 98 so that the same are de-energized and the blades20I and 204 open. Opening of the blade 204 breaks the energizing circuitfor the valve solenoid 201 and the pump solenoid 208. De-energization ofthe valve solenoid 201 allows the spring I63 to return the valve memberI8I toa position in which pressure fluid from the auxiliary pump I68passes through the line I intothe upper portion of the ejector cylinders18, thereby. returning the elector plungers 11 to their lowermostposition.

De-energization of the pump solenoid 208 allows the spring (not shown)in the servo-motor I 38 of the main pump II8 to shift said main pump tofull delivery retraction stroke position. so that pressure fluid fromthe pump II 8 now flows into the push-back cylinders I23 for retractingthe platen 33, while a part of the pressure fluid flows through conduitsI24 and 50 and the bore 49 into the upper portion of the turret cylinder43, thereby lifting the latter. The platen 83 now returns to its initialposition in the manner previously described. The press ram I03, theturret 24 and the ejectors are then in the position shown in To startanew cycle, the operator presses the starter switch blade ,I9 2 so as tointerconnect the terminals HI and I94, .Current will then flow from theconduit'I45 through line I89, blade I92, line 209, the now closedcontrol switch 2I0, line 2I2 and, on one hand, through valve solenoid 2I4 to the main supply line I50 and, on the other 11,530 solenoid 2I5likewise to the main supply Energization of the valve solenoid 2| 4which,

the turret 24, which then moves from its present to its previousindexing position. As soon-as the turret 24 leaves its present indexingposition. the control switch blade I95 closes again. When the turret hasreached its new indexing position, the cam 2I I opens the control switch2 I which, however, has no effect on the circuit.

Energization of the solenoid 2I5 causes blade 2I6 to interconnect thelines M8 and 2 I3, thereby establishing a holding circuit for thesolenoid 2 I 5, which holding circuit comprises the line I45, tonnagecontrol switch 203, line 2I'8, blade 2H5, line 2I3, solenoid 2I5, line222 and the main supply line I50. Energization of thesolenoid 2I5 alsocauses the blade 2II to interconnect the lines 2I9 and 220.

Since in the pressing cycle the switch I85 was open, closure of theblade 2I'I does not establish a circuit. However, as soon as the rack 56has again reached its left end position while the turret 24 has reachedits corresponding indexing position, the rack 56 has closed the switchI85, thereby establishing a circuit comprising the main supply line 5,pump solenoid 208, line 2 I 9, blade 2II, line 220, switch I85, line HIand main supply line, I50.

Energization of the pump solenoid 208 puts the pump on full deliveryforward stroke in the manner previously described so that the ram I03now starts its pressing stroke. The operation then follows the samelines as described above. In other words, at the end of the pressingoperation the tonnage control switch 203 opens, thereby breaking theholding circuit for the solenoid 2I5 so that the switch blades 2 I6 and2 I I move to open position. Opening of the switch blade 2|! causesde-energization of the pump solenoid 208 and de-energization of thevalve solenoid 201.

De-energization of the pump solenoid 208 allows the spring in theservomotor I38 of the pump 8 to move the pump to full deliveryretraction stroke position, while de-energization of the solenoid 201allows the spring I63 to shift the valve member IGI so as to causepressure fluid to flow through the line 85 into the ejector cylinders 16for moving the ejector plungers TI to their lowermost position. The ramI03 now completes its retraction stroke at the end of which the pump H8is moved to substantially neutral position as described above. The ramI03, the turret 24, the ejectors and the valve plungers 6i and 62 nowagain occupy the position shown in Figure 9.

Assuming now that instead of starting the last mentioned cycle byinterconnecting the terminals I9I and I94, the blade I92 was by mistakeactuated so as to interconnect the terminals I90 and I93, this wouldestablish no circuit in contrast to the electrical circuit of Figure 9so that the press would not move at all. The operator would then at onceknow that he has made a wrong contact and without causing any deadstroke or damage he can immediately actuate the starter switch blade I92to make the proper contact.

It will be understood that the present inven tion is not limited to thespecific embodiment shown in the drawings but embraces also suchmodifications as come within the scope of the claims.

Having thus fully described my invention, what I claim as new and desireto secure by Letters Patent is:

1. In combination in a press, a frame, a workholding turret mounted insaid frame, a movable press ram, fluid pressure responsive means forrotatably supporting said turret, said turret beingnormally supported onsaid frame, anti-friction bearingmeans for limiting motion of saidturret out of engagement withlsaid frame whereby to selectively supportsaid turret by said fluid pressure responsive means for indexingoperations or on said frame for pressing operations, saidpressure-responsive means being operable in response to a predeterminedpressure on said ram for causing said turret to come into enga ementwith said frame.

2. In combination in a press, a frame, a workholding turret mounted insaid frame, a movable press ram, fluid pressure means for rotatablysupporting and raising said turret, whereby said turret is supported byfluid under pressure in its raised position for indexing operations, andsupported on said frame in its lowered position for pressing operations,and means operable in response to a predetermined pressure on said ramfor causing the lowering of said turret.

3. In combination in a. press, a frame, a. workholding turretmounted insaid frame, a movable press ram, fluid pressure responsive means forrotatably supporting said turret, said turret being normally supportedby said frame, means for selectively bringing said turret outofengagement with said frame whereby to selectively support said turret byfluid under pressure for indexing operations and means operable inresponse to a predetermined pressure on said ram for causing said turretto come into engagement with said frame, and a hydraulic motor means forindexing said turret while said turret is supported on said fluid underpressure.

4. In combination in a press, a frame, a workholding turret mounted insaid frame, a movable press ram, fluid pressure operated means forraising and rotatably supporting said turret, whereby said turret issupported by fluid under pressure in its raised position for indexingoperations, and supported on said frame in its lowered position forpressing operations, said fluid pressure operated means being operablein response to a predetermined pressure on said ram f0] causing thelowering of said turret onto saic frame, and hydraulic motor meansconnected tc index said turret by a predetermined adiustablr angle.

5. In combination in a press, a frame, -a workholding turret mounted insaid frame, a movablr press ram, anti-friction bearings, fluid pressurimeans for raising said turret against said bearings whereby said turretis supported by fluic under pressure in its raised position for anindexing operation, and supported onsaid frame in it: lowered positionfor a pressing operation, saic fluid pressure means being operable inrespons4 to a predetermined pressure on said ram to lowe: said turret,and hydraulic motor means for in dexing saidturret, said motor meansincluding piston means and adjustable means for limitin! the travel ofsaid piston means.

6. In combination a press, a frame, a worl holding turret mounted insaid frame, a movabli press plunger, means for introducing a body 0fluid under pressure between said frame and saii turret for directlyrotatably supporting said tur ret, said means operating to raise saidturre whereby said turret is supported on said body ii its raisedposition for indexing operations, am supported on said frame in itslowered positioi for pressing operations, said turret being lowerei inresponse to a predetermined pressure by Sail plunger for causing thelowering of said turrei and hydraulic motor means for indexing saidturret, said motor means including piston means and adjustable means forlimiting the travel of said piston means in both directions of movementof said piston means.

7. In combination with a press, a frame, a work holding turret rotatablymounted on said frame, a cylinder part, a piston part reciprocablewithin said cylinder part on an axis of rotation of said turret, one ofsaid parts being attached to said turret, the other of said parts beingattached to said frame, whereby, when fluid pressure is introduced intosaid cylinder. the parts are reciprocated to float said turret directlyby fluid pressure..

8. In a press, a support, a work holding turret normally resting on saidsupport during a pressing operation, and fluid pressure means forraising said turret from said support and directly floatingly supportingthe same on fluid under pressure for indexing movement thereof.

9. In a press, a support, a work holding turret normally resting on saidsupport during a press ing operation, fluid pressure means forraisingsaid turret from said support and directly floatingly supporting thesame onfluid under pressure for indexing movement thereof, and stopmeans comprising an anti-friction bearing limiting the raising movementof said turret.

10. In a press, a support, a 'work holding turret normally resting onsaid support during a pressing operation, fluid pressure means forraising said turret from said support'and directly floatingly supportingthe same on fluid under pressure for indexing movement thereof, andpressure fluidactuated means connected to said turret to impart indexingmovement thereto.

11. In a press, a frame,-a ram, a work holding turret movable to aplurality of predetermined indexing positions to present a workpiecetherein to said ram for pressing, said turret resting on said frameduring pressing of the workpiece, and means for introducing a body offluid under pressure between said'turret and frame to raise said turretfrom said frame and movably supp rt the same directly upon said bodyduring indexing movement.

12. In a press, a frame, a work holding turret mounted on said frame foraxial movement and rotational indexing movement, means for introducing abody of fluid under pressure between said turret and frame for movingsaid turret axially and thereby directly supporting said tur-.

rat on said body. and fluid pressure responsive means for rotating saidturret while so supported and holding the same 'in indexed position.

WALTER ERNST.

